static bool __CanCastTo(DmdType from, DmdType to)
{
if ((object)from == null)
{
throw new ArgumentNullException(nameof(from));
}
if ((object)to == null)
{
throw new ArgumentNullException(nameof(to));
}
bool res;
var r = from.__CanCastToNoGC(to);
if (r == __CastResult.MaybeCast)
{
res = from.__CanCastTo(to);
}
else
{
res = r == __CastResult.CanCast;
}
if (!res && to.IsNullable && !from.__IsTypeDesc())
{
if (__IsNullableForType(to, from))
{
res = true;
}
}
return(res);
}
static bool __IsNullableForType(DmdType type, DmdType param)
{
if (type.__IsTypeDesc())
{
return(false);
}
if (!type.IsConstructedGenericType)
{
return(false);
}
return(__IsNullableForTypeHelper(type, param));
}
bool __CanCastTo(DmdType type)
{
if (this == type)
{
return(true);
}
if (__IsTypeDesc())
{
return(__TypeDesc_CanCastTo(type));
}
if (type.__IsTypeDesc())
{
return(false);
}
return(__CanCastToClassOrInterface(type));
}
__CastResult __CanCastToNoGC(DmdType type)
{
if (this == type)
{
return(__CastResult.CanCast);
}
if (__IsTypeDesc())
{
return(__TypeDesc_CanCastToNoGC(type));
}
if (type.__IsTypeDesc())
{
return(__CastResult.CannotCast);
}
return(__CanCastToClassOrInterfaceNoGC(type));
}
__CastResult __TypeDesc_CanCastToNoGC(DmdType toType)
{
Debug.Assert(this != toType);
if (IsGenericParameter)
{
if (toType == AppDomain.System_Object)
{
return(__CastResult.CanCast);
}
if (toType == AppDomain.System_ValueType)
{
return(__CastResult.MaybeCast);
}
foreach (var constraint in GetGenericParameterConstraints())
{
if (constraint.__CanCastToNoGC(toType) == __CastResult.CanCast)
{
return(__CastResult.CanCast);
}
}
return(__CastResult.MaybeCast);
}
if (!toType.__IsTypeDesc())
{
if (!IsArray)
{
return(__CastResult.CannotCast);
}
return(__CanCastToClassOrInterfaceNoGC(toType));
}
var toKind = toType.__GetInternalCorElementType();
var fromKind = __GetInternalCorElementType();
if (!(toKind == fromKind || (toKind == DDN.ElementType.Array && fromKind == DDN.ElementType.SZArray)))
{
return(__CastResult.CannotCast);
}
switch (toKind)
{
case DDN.ElementType.Array:
if (GetArrayRank() != toType.GetArrayRank())
{
return(__CastResult.CannotCast);
}
goto case DDN.ElementType.SZArray;
case DDN.ElementType.SZArray:
case DDN.ElementType.ByRef:
case DDN.ElementType.Ptr:
return(__CanCastParamNoGC(GetElementType(), toType.GetElementType()));
case DDN.ElementType.Var:
case DDN.ElementType.MVar:
case DDN.ElementType.FnPtr:
return(__CastResult.CannotCast);
default:
return(__CastResult.CanCast);
}
}
bool __TypeDesc_CanCastTo(DmdType toType)
{
if (this == toType)
{
return(true);
}
if (IsGenericParameter)
{
if (toType == AppDomain.System_Object)
{
return(true);
}
if (toType == AppDomain.System_ValueType)
{
if ((GenericParameterAttributes & DmdGenericParameterAttributes.NotNullableValueTypeConstraint) != 0)
{
return(true);
}
}
foreach (var constraint in GetGenericParameterConstraints())
{
if (constraint.__CanCastTo(toType))
{
return(true);
}
}
return(false);
}
if (!toType.__IsTypeDesc())
{
if (!IsArray)
{
return(false);
}
if (__CanCastToClassOrInterface(toType))
{
return(true);
}
if (toType.IsInterface)
{
if (__ArraySupportsBizarreInterface(this, toType))
{
return(true);
}
}
return(false);
}
var toKind = toType.__GetInternalCorElementType();
var fromKind = __GetInternalCorElementType();
if (!(toKind == fromKind || (toKind == DDN.ElementType.Array && fromKind == DDN.ElementType.SZArray)))
{
return(false);
}
switch (toKind)
{
case DDN.ElementType.Array:
if (GetArrayRank() != toType.GetArrayRank())
{
return(false);
}
goto case DDN.ElementType.SZArray;
case DDN.ElementType.SZArray:
case DDN.ElementType.ByRef:
case DDN.ElementType.Ptr:
return(__CanCastParam(GetElementType(), toType.GetElementType()));
case DDN.ElementType.Var:
case DDN.ElementType.MVar:
case DDN.ElementType.FnPtr:
return(false);
default:
return(true);
}
}
